Leave it to Guillermo del Toro to use the word “romantic” when talking about massive, towering robots.

“What I wanted to do was to make gothic tech,” Del Toro said of his new film “Pacific Rim,” due out July 12. “What we went for is a very, very romantic look. I wanted to have a lot of crazy rain, wind, all the drama of an Emily Bronte movie in a high-tech movie.”

To the casual observer, “Pacific Rim” might not recall 19th century British literature so much as the ultimate “Godzilla” meets “Transformers” mash-up. The story takes place in a near future, after a race of giant alien monsters has invaded our world via an inter-dimensional portal, prompting mankind to build equally enormous robots called Jaegers to defeat them.

The hulking mechanized weapons are manned by an elite team of pilots, including Charlie Hunnam’s Raleigh Becket and Rinko Kikuchi’s Mako Mori, who represent humanity’s best line of defense against the beastly threat.

Del Toro’s first film as a director since 2008’s “Hellboy II: The Golden Army,” “Pacific Rim” is a roughly $180-million love letter to Japan’s kaiju movies, of which “Godzilla” remains perhaps the most famous example.

The director has always been a passionate advocate for monsters — unusual creations play a central role in nearly all his films — and “Pacific Rim” is no exception. He’s dreamed up a wild menagerie of ferocious kaiju, each of which stands roughly 25 stories tall.

“The monsters are more powerful than I’ve ever designed,” he said. “We use cars and buildings as you would use walls in a bar fight or glasses and tables in a bar fight.”

Del Toro, who co-wrote the screenplay with Travis Beacham, shot “Pacific Rim” almost entirely at Pinewood Toronto Studios, where the production used the facility’s eight soundstages over five months from November of 2011 to April of last year.

“We built parts of the robots, and the only thing that would fit in the largest stage in North America was the feet,” Del Toro said. “That’s it.”

Since then, he’s been conjuring the rest of the elaborate world in post-production, working with CG animators and visual effects artists to digitally execute the movie’s epic battle sequences and then to convert those scenes into 3-D.

With about seven robots sharing screen time, duking it out in stormy environments — one fight takes place underwater — the task isn’t easy.

But getting it right is critical. “Pacific Rim” could be the first installment in a new franchise for Legendary Pictures and Warner Bros., though Del Toro has said that he doesn’t think a sequel will officially be greenlighted until the box-office returns are in this summer.

“Normally in a movie of this size, you’ll get one spaceship, one or two aliens,” Del Toro said. “The challenge with this movie was to create all those robots, all the technical stuff we needed for them, all these kaijus, the depths of the ocean. The complexity of the movie was huge.”